Suspended or pendant scaffolds of the type which are suspended by cables from the roof or cornices of buildings and move vertically along the walls thereof are frequently used by painting, cleaning, or window washing crews or for other activities where it is necessary to move personnel or equipment across the outer surface of a building or other structure. Very basically, the scaffolding rigs include a pair of side frames which are hung from the cables and include a stage or platform extending between the side frames on which is supported personnel or equipment. During the last few years, architects have often designed buildings that are primarily faced with glass or which have large expanses of windows within only narrow walls or mullions extending between them. When a suspended scaffolding rig is moving along the walls of such buildings there is considerable danger of the scaffold swinging into a window and breaking the window or otherwise damaging the face of the building.
Certain of the scaffolds known in the prior art include a roller or wheel adjacent the forward or building side of the platform or stage to act as a protective "bumper" between the rig and the building mullions or facing. Most of these rollers are permanently attached to the scaffold and cannot be laterally adjusted to align with the solid structural portions between glass panels of the building walls. Therefore the same scaffold is not easily adapted for use with a building having mullions or facings of varying dimensions. When a scaffold rig is to be used solely on a particular building the inability to laterally adjust the position of the rollers thereon presents no significant problem because the rollers will be initially attached to the scaffolding such that they coincide with the wall structure of the building. However, when a rig is to be operated by a contractor on several types of buildings or structures this can pose a significant problem.
To provide lateral adjustability some of the roller assemblies in the prior art are clamped onto the inner edge of the platform or are mounted on relatively short and, occasionally, not very strong shankpieces. Upon impact of the scaffold against a building, the aforementioned clamps may unlock or dislodge, or the shankpieces may snap in two and thereby render the bumper useless.
To the inventor's knowledge, there is no scaffold protective roller in the prior art which is successfully laterally adjustable along the forward or inner wall of the scaffold stage according to the wall structure of the building, in addition to being securely locked into position such that the roller assembly does not break or dislodge on impact.